Pipe and clamp type scaffolding systems are extensively used in the building sector. They are able to be easily adapted to conform to confined spaces and provide a modest amount of flexibility in terms of the shape of scaffolding structures that can be constructed. However these systems require significant expertise to erect correctly and are usually erected by experienced people, largely because of the large degree of flexibility that is available. This requires for expert knowledge to ensure a correctly erected scaffolding structure is put in place. Modular systems remove the need for such high degree of expertise. Modular systems consist of prefabricated components usually of specific lengths and are inter-operative and inter-connectable with each other. With increasing labour costs there is a preference for scaffolding systems to be easy to erect.
Modular systems will comprise of a number of different components that can be connected together to form at least part of a scaffold structure. Such a scaffold structure may comprise of a plurality of standards 1 as shown in FIG. 1 that may be connected together via ledgers 2. Ledgers may also be referred to as transoms. A scaffold structure may also include guard rails 3. The standards, ledgers and guardrails are preferably made from metal pipe.
A scaffolding system exists that allows for the connection of ledgers, transoms and standards in a convenient manner. Such is shown with reference to FIGS. 1 to 5. Standards 1 may have nodal points 5 provided at at least one and preferably a plurality of separated locations along its length. The nodal points are defined by a rosette 6. This is a ring-like member as shown in FIG. 2. The rosette 6 has a central aperture 7 through which the pipe part of a standard extends. The rosette 6 is usually welded to the standard so as to be secured in place. The rosette 6 may be of a planar configuration. Its plane extends in a direction such that the elongate direction of the standard 1 is normal thereto. The rosette 6 includes at least one and preferably a plurality of holes. These may be in the form of slots 8. With the rosette 6 engaged to a standard the slots preferably project radially outward from the standard. The pipe part of a standard may define part of the boundary of the slot 8.
The rosette 6 shown in FIG. 2 includes four slots, each equispaced and extending radially away from the standard. The four slots facilitate right angled connections of ledgers to the vertical standard. Some rosettes may include more slots, but the more slots that are included, the weaker the rosette becomes.
FIG. 3 illustrates a ledger 2 that includes a head at each of its distal ends. Such a head may comprise projections 10. These projections 10 are of a shape to allow for these to be located into a slot 8 of a rosette 6. Each projection 10 may be welded to the end of the pipe section of the ledger. The projection 10 presents a leg 11 that can be received into a slot 8 of a rosette 6. The projection 11 may be tapered so that it can be conveniently located into the slot and become wedged to the standard. An aperture 12 may be provided through the projection 11 to allow for a fastener to extend through. Such can ensure that the ledger cannot be removed from the rosette 6. The fastener may for example be a split pin or ring or other arrangement that can help secure the ledger to the ring member 6. As can be seen in FIG. 7 where a rosette 6 has four slots, it is possible for four ledgers to each extend therefrom and away from the standard. Ledgers 2 are of a fixed length so that the distance between adjacent erected standards is fixed.
The projections 10 are planar member (usually cut from a sheet metal). The complimentary shaped slot 8 results in a snug fit being established between the projection 10 and the rosette 6 so as to ensure that the direction which the ledger extends from the standard is fixed. This assists in the construction process of the scaffold structure and provides some degree of rigidity to the scaffold structure.
Alternatively, the head may be of a configuration to slide over the rosette and has an aperture that can align with the slots of the rosette and a separate wedge can then be inserted through both the head and the rosette slots to couple the ledger to the standard. This is shown for example in US 2011/0262215.
The location of complimentary shaped wedge or projection of a ledger with a slot of a rosette will ensure that little or no play exists between the ledger and the standard.
In the example as shown in FIGS. 1-5 ledgers can only extend at right angles or parallel to each other from a standard.
For scaffolding erected adjacent a building structure or more particularly for a scaffolding erected inside an elevator shaft of a building, it is important for the structure to be tied to the building so as to receive some stability from the building structure. In particular, lateral stability.
To achieve this support from a building structure short arms are typically used to extend between the scaffolding and the walls of the elevator shaft. Towards one end of a short arm a clamp coupling is usually used to secure the short arm to a ledger or standard of the scaffolding structure. The other end of the arm may be provided with an anchoring plate adapted to be bolted to a wall of the elevator shaft. Disadvantages of this way of laterally stabilising a scaffold structure include:
a) a significant amount of work is required to connect the short arms to the scaffolding structure,
b) the arm may not be firmly secured to the scaffolding because of a loose clamp coupling,
c) short arms of different lengths may have to be used or may need to be trimmed onsite to ensure that it is of a suitable length for providing the lateral stability,
d) the scaffolding may still not be fully secured in a lateral direction as equal and opposite forces may need to be exerted onto the scaffolding in a horizontal direction in order to keep the scaffolding firmly positioned in the elevator shaft.
For other building elements located adjacent a building, support may be required from time to time from the building structure also. For example for a swing stage suspended adjacent a building and that may travel up a down a building for maintenance, window cleaning and similar, the swing stage may be desirous of contact with the building to reduce the degree of undesired movement of the swing stage. Such support will need to cater for the fact that the swing stage travels up and down relative the building.
It is accordingly an object of the present invention to provide at least one component for a modular scaffolding system that address one or more of the abovementioned disadvantages and/or to provide the public with a useful choice.